61,818 research outputs found
Butterflies of the Rocky Mountain States. Edited by Clifford D. Ferris and F. Martin Brown. University of Oklahoma Press, Norman. 464 pages, incl. 4 color plates. 1981. 15.95 (paper).
(excerpt)
The long awaited guide to the butterflies of the Rocky Mountains will be received with great delight by many lepidopterists who collect butterflies in this rugged and beautiful region
The World of Moths. Michael Dickens and Eric Storey. Macmillan Publishing Co., Inc., New York, 1974. 128 p., 103 plates. $6.95.
(excerpt)
This little book will undoubtedly please the amateur collector and rearer of the exotically and exquisitely colored species such as found in the Saturniidae and Sphing- idae. Of the 103 colored photographic plates, 69 illustrate species from these two popular families. Each species is figured on a white background in sharp and vivid color. One species is figured on a page, except for Epicopeia polydora, which includes a figure of its mimetic model Papilio rhetenor
AN INDEX TO THE DESCRIBED LI1:E HISTORIES, EARLY STAGES AND HOSTS OF THE MACROLEPIDOPTERA OF THE CONTINENTAL UNITED STATES AND CANADA,\u27\u27 by Harrison Morton Tietz, 1972
AN INDEX TO THE DESCRIBED LI1:E HISTORIES, EARLY STAGES AND HOSTS OF THE MACROLEPIDOPTERA OF THE CONTINENTAL UNITED STATES AND CANADA,\u27\u27 by Harrison Morton Tietz, 1972. Two volumes, 1041 p., published by A. C. Allyn for the Allyn Museum of Entomology, Sarasota, Florida. Distributed exclusively in North America by Entomological Reprint Specialists, P.O. Box 77971, Dockweiler Station, Los Angeles, California 90007. Price: $25.00 U.S. per set
The trumping relation and the structure of the bipartite entangled states
The majorization relation has been shown to be useful in classifying which
transformations of jointly held quantum states are possible using local
operations and classical communication. In some cases, a direct transformation
between two states is not possible, but it becomes possible in the presence of
another state (known as a catalyst); this situation is described mathematically
by the trumping relation, an extension of majorization. The structure of the
trumping relation is not nearly as well understood as that of majorization. We
give an introduction to this subject and derive some new results. Most notably,
we show that the dimension of the required catalyst is in general unbounded;
there is no integer such that it suffices to consider catalysts of
dimension or less in determining which states can be catalyzed into a given
state. We also show that almost all bipartite entangled states are potentially
useful as catalysts.Comment: 7 pages, RevTe
Radiative decay of the X(3872) as a mixed molecule-charmonium state in QCD Sum Rules
We use QCD sum rules to calculate the width of the radiative decay of the
meson X(3872), assumed to be a mixture between charmonium and exotic molecular
states with . We find that in a small
range for the values of the mixing angle, , we get the
branching ratio , which is in agreement, with the experimental
value. This result is compatible with the analysis of the mass and decay width
of the mode performed in the same approach.Comment: 7 pages, 9 figures; revised version accepted for publication in Phys.
Rev.
Information Flow of quantum states interacting with closed timelike curves
Recently, the quantum information processing power of closed timelike curves
have been discussed. Because the most widely accepted model for quantum closed
timelike curve interactions contains ambiguities, different authors have been
able to reach radically different conclusions as to the power of such
interactions. By tracing the information flow through such systems we are able
to derive equivalent circuits with unique solutions, thus allowing an objective
decision between the alternatives to be made. We conclude that closed timelike
curves, if they exist and are well described by these simple models, would be a
powerful resource for quantum information processing.Comment: Now includes appendix proving Deutsch's maximum entropy conjectur
(2317) meson production at RHIC
Production of (2317) mesons in relativistic heavy ion collisions at
RHIC is studied. Using the quark coalescence model, we first determine the
initial number of (2317) mesons produced during hadronization of
created quark-gluon plasma. The predicted (2317) abundance depends
sensitively on the quark structure of the (2317) meson. An
order-of-magnitude larger yield is obtained for a conventional two-quark than
for an exotic four-quark (2317) meson. To include the hadronic effect
on the (2317) meson yield, we have evaluated the absorption cross
sections of the (2317) meson by pion, rho, anti-kaon, and vector
anti-kaon in a phenomenological hadronic model. Taking into consideration the
absorption and production of (2317) mesons during the hadronic stage of
heavy ion collisions via a kinetic model, we find that the final yield of
(2317) mesons remains sensitive to its initial number produced from the
quark-gluon plasma, providing thus the possibility of studying the quark
structure of the (2317) meson and its production mechanism in
relativistic heavy ion collisions.Comment: 12 pages, 6 figure
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